package com.atguigu.gulimall.search.service.impl;

import com.alibaba.fastjson.JSON;
import com.atguigu.common.to.es.SkuEsModel;
import com.atguigu.gulimall.search.config.ElasticsearchConfig;
import com.atguigu.gulimall.search.constant.EsConstants;
import com.atguigu.gulimall.search.service.MallSearchService;
import com.atguigu.gulimall.search.vo.SearchParam;
import com.atguigu.gulimall.search.vo.SearchResult;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.NestedQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.nested.NestedAggregationBuilder;
import org.elasticsearch.search.aggregations.bucket.nested.ParsedNested;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedLongTerms;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

@Service
public class MallSearchServiceImpl implements MallSearchService {

    @Autowired
    RestHighLevelClient restHighLevelClient;
    @Override
    public SearchResult search(SearchParam searchParam) {
        //一、动态构建出查询需要的DsL语句
        SearchResult result = null;
        //1、准备检索请求
        SearchRequest searchRequest = buildSearchRequest(searchParam);
        try {
            //2、执行检索请求
            SearchResponse response = restHighLevelClient.search(searchRequest, ElasticsearchConfig.COMMON_OPTIONS);
            //3、分析响应数据封装成我们需要的格式
            result = buildSearchResult(response, searchParam);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }

    /**
     * 准备检索请求
     * 模糊匹配，过滤（按照属性，分类，品牌，价格区间，库存)，排序，分页，高亮，聚合分析
     * @return
     */
    private SearchRequest buildSearchRequest(SearchParam searchParam) {
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        /**
         * 过滤（按照属性，分类，品牌，价格区间，库存)
         */
        //1.构建bool - query
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
        //1.1 must-模糊匹配
        if (!StringUtils.isEmpty(searchParam.getKeyword())){
            boolQuery.must(QueryBuilders.matchQuery("skuTitle", searchParam.getKeyword()));
        }
        //1.2.1 bool - filter 三级分类ID查询
        if (searchParam.getCatalog3Id() != null){
            boolQuery.filter(QueryBuilders.termQuery("catalogId",searchParam.getCatalog3Id()));
        }
        //1.2.2 bool - filter 品牌ID查询
        if (searchParam.getBrandId() != null && searchParam.getBrandId().size()>0){
            boolQuery.filter(QueryBuilders.termsQuery("brandId",searchParam.getBrandId()));
        }
        //1.2.3 bool - filter 库存查询
        if (searchParam.getHasStock() != null) {
            boolQuery.filter(QueryBuilders.termQuery("hasStock",searchParam.getHasStock()==1 ? true : false));
        }

        //1.2.4 bool - filter 价格区间查询
        if (!StringUtils.isEmpty(searchParam.getSkuPrice())){
            RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("skuPrice");
            String[] s = searchParam.getSkuPrice().split("_");
            if (s.length == 2){
                rangeQuery.gte(s[0]).lte(s[1]);
            } else {
                if (searchParam.getSkuPrice().startsWith("_")){
                    rangeQuery.lte(s[0]);
                }
                if (searchParam.getSkuPrice().endsWith("_")){
                    rangeQuery.gte(s[0]);
                }
            }
            boolQuery.filter(rangeQuery);
        }
        //1.2.5 bool - filter 按照指定的属性查询
        if (searchParam.getAttrs()!=null && searchParam.getAttrs().size()>0){
            for (String attr : searchParam.getAttrs()) {
                BoolQueryBuilder nestedBoolQuery = QueryBuilders.boolQuery();
                // attrs=1_5寸:8寸&attrs=2_16G:8G
                //attr = 1_5寸:8寸
                String[] s = attr.split("_");
                String attrId = s[0];//检索属性的ID
                String[] attrValues = s[1].split(":");//该属性的检索的值
                nestedBoolQuery.must(QueryBuilders.termsQuery("attrs.attrId", attrId));
                nestedBoolQuery.must(QueryBuilders.termsQuery("attrs.attrValue", attrValues));
                NestedQueryBuilder nestedQuery = QueryBuilders.nestedQuery("attrs", nestedBoolQuery, ScoreMode.None);
                boolQuery.filter(nestedQuery);
            }
        }
        //把所有的条件进行封装
        sourceBuilder.query(boolQuery);

        /**
         * 排序，分页，高亮
         */
        //2.1 排序
        if (!StringUtils.isEmpty(searchParam.getSort())){
            String sort = searchParam.getSort();
            //sort = hotScore_asc/desc
            String[] s = sort.split("_");
            SortOrder order = s[1].equalsIgnoreCase("asc") ? SortOrder.ASC : SortOrder.DESC;
            sourceBuilder.sort(s[0], order);
        }
        //2.2、分页pageSize:5
        //  pageNum:1   from:0   size:5     [0,1,2,3,4]
        //  pageNum:2   from:5  size:5
        //  from = (pageNum-1)*size
        sourceBuilder.from((searchParam.getPageNum()-1)*EsConstants.PRODUCT_PAGE_SIZE);
        sourceBuilder.size(EsConstants.PRODUCT_PAGE_SIZE);

        //2.3、高亮
        if (!StringUtils.isEmpty(searchParam.getKeyword())){
            HighlightBuilder builder = new HighlightBuilder();
            builder.field("skuTitle");
            builder.preTags("<b style='color:red'>");
            builder.postTags("</b>");
            sourceBuilder.highlighter(builder);
        }

        /**
         * 聚合分析
         */
        //1、品牌聚合
        TermsAggregationBuilder brand_agg = AggregationBuilders.terms("brand_agg");
        brand_agg.field("brandId").size(50);
        //1.1、品牌聚合的子聚合
        brand_agg.subAggregation(AggregationBuilders.terms("brand_name_agg").field("brandName").size(1));
        brand_agg.subAggregation(AggregationBuilders.terms("brand_img_agg").field("brandImg").size(1));
        sourceBuilder.aggregation(brand_agg);

        //2、分类聚合
        TermsAggregationBuilder catalog_agg = AggregationBuilders.terms("catalog_agg").field("catalogId").size(50);
        //2.1、分类聚合的子聚合
        catalog_agg.subAggregation(AggregationBuilders.terms("catalog_name_agg").field("catalogName").size(1));
        sourceBuilder.aggregation(catalog_agg);
        //3、属性聚合 attr_agg
        NestedAggregationBuilder attr_agg = AggregationBuilders.nested("attr_agg", "attrs");
        //聚合出当前所有attrId
        TermsAggregationBuilder attr_id_agg = AggregationBuilders.terms("attr_id_agg").field("attrs.attrId").size(50);
        //3.1、分类聚合的子聚合
        //聚合分析出当前attr_id对应的
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_name_agg").field("attrs.attrName").size(1));
        //聚合分析出当前attr_id对应的所有可能的属性值attrValue
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_value_agg").field("attrs.attrValue").size(50));

        attr_agg.subAggregation(attr_id_agg);
        sourceBuilder.aggregation(attr_agg);

        String s = sourceBuilder.toString();
        System.out.println("构建的DSL语句：" + s);
        SearchRequest searchRequest = new SearchRequest(new String[]{EsConstants.PRODUCT_INDEX}, sourceBuilder);
        return searchRequest;
    }

    /**
     * 构建结果数据
     * @param response
     * @return
     */
    private SearchResult buildSearchResult(SearchResponse response, SearchParam searchParam) {
        SearchResult result = new SearchResult();
        SearchHits hits = response.getHits();
        List<SkuEsModel> skuList = new ArrayList<>();
//        //1、返回的所有查询到的商品
        SearchHit[] hitsSource = hits.getHits();
        if (hitsSource != null && hitsSource.length > 0) {
            for (SearchHit hit : hitsSource) {
                String source = hit.getSourceAsString();
                SkuEsModel skuEsModel = JSON.parseObject(source, SkuEsModel.class);
                HighlightField skuTitle = hit.getHighlightFields().get("skuTitle");
                if (skuTitle != null) {
                    String string = skuTitle.getFragments()[0].string();
                    skuEsModel.setSkuTitle(string);
                }
                skuList.add(skuEsModel);
            }
        }
        result.setProducts(skuList);
//        //2、当前所有商品涉及到的所有属性信息
        List<SearchResult.AttrVo> attrVos = new ArrayList<>();
        ParsedNested attr_agg = response.getAggregations().get("attr_agg");
        ParsedLongTerms attr_id_agg = attr_agg.getAggregations().get("attr_id_agg");
        for (Terms.Bucket bucket : attr_id_agg.getBuckets()) {
            SearchResult.AttrVo attrVo = new SearchResult.AttrVo();
            //得到属性的ID
            long attrId = bucket.getKeyAsNumber().longValue();
            attrVo.setAttrId(attrId);
            //得到属性的名
            ParsedStringTerms attr_name_agg = bucket.getAggregations().get("attr_name_agg");
            String attrName = attr_name_agg.getBuckets().get(0).getKeyAsString();
            attrVo.setAttrName(attrName);
            //得到属性的所有值
            ParsedStringTerms attr_value_agg = bucket.getAggregations().get("attr_value_agg");
            List<String> attrValues = attr_value_agg.getBuckets().stream().map(item -> {
                String keyAsString = ((Terms.Bucket) item).getKeyAsString();
                return keyAsString;
            }).collect(Collectors.toList());
            attrVo.setAttrValue(attrValues);
            attrVos.add(attrVo);
        }
        result.setAttrList(attrVos);
//        //3、当前所有商品涉及到的所有品牌信息、
        List<SearchResult.BrandVo> brandVos = new ArrayList<>();
        ParsedLongTerms brand_agg = response.getAggregations().get("brand_agg");
        List<? extends Terms.Bucket> buckets = brand_agg.getBuckets();
        for (Terms.Bucket bucket : buckets) {
            SearchResult.BrandVo brandVo = new SearchResult.BrandVo();
            //得到品牌ID
            long brandId = bucket.getKeyAsNumber().longValue();
            brandVo.setBrandId(brandId);
            //得到品牌名
            ParsedStringTerms brand_name_agg = bucket.getAggregations().get("brand_name_agg");
            String brandName = brand_name_agg.getBuckets().get(0).getKeyAsString();
            brandVo.setBrandName(brandName);
            //得到品牌图片
            ParsedStringTerms brand_img_agg = bucket.getAggregations().get("brand_img_agg");
            String brandImg = brand_img_agg.getBuckets().get(0).getKeyAsString();
            brandVo.setBrandImg(brandImg);

            brandVos.add(brandVo);
        }
        result.setBrandList(brandVos);
//        //4、当前所有商品涉及到的所有分类信息.
        List<SearchResult.CatalogVo> catalogVos = new ArrayList<>();
        ParsedLongTerms catalog_agg = response.getAggregations().get("catalog_agg");
        for (Terms.Bucket bucket : catalog_agg.getBuckets()) {
            SearchResult.CatalogVo catalogVo = new SearchResult.CatalogVo();
            String keyAsString = bucket.getKeyAsString();
            catalogVo.setCatalogId(Long.parseLong(keyAsString));
            ParsedStringTerms catalog_name_agg = bucket.getAggregations().get("catalog_name_agg");
            String catalogName = catalog_name_agg.getBuckets().get(0).getKeyAsString();
            catalogVo.setCatalogName(catalogName);
            catalogVos.add(catalogVo);
        }
        result.setCatalogList(catalogVos);
        //以上从聚合信息中获取
//        //5、分页信息-页码
        result.setPageNum(searchParam.getPageNum());
//        //5、分页信息-总记录树
        long total = hits.getTotalHits().value;
        result.setTotal(total);
//        //5、分页信息-总.贝码
        long pages = total / EsConstants.PRODUCT_PAGE_SIZE;
        result.setTotalPage(total % EsConstants.PRODUCT_PAGE_SIZE == 0 ? pages : pages + 1);

        Long totalPage = result.getTotalPage();
        List<Long> pageList = new ArrayList<>();
        for (long i = 1; i <= totalPage; i++) {
            pageList.add(i);
        }
        result.setPageNavs(pageList);
        return result;
    }

}
